The dissociation energy of `CH_(40` and `C_(2)H_(6)` are respectively `360` and `620 kcal//mol.` The bond energy of `C-C` bond is `:`

Options

A. 260 kcal/mol
B. 180 kcal/mol
C. 130 kcal/mol
D. 80 kcal/mol

Answer

D

Explanation

`CH_4 rarr C +4H, Delta H =360 kcal `
`H_(C -H)= 90 kcal `
`C_2 H_6 rarr 2C +6 H, Delta H= 620 kca l`
`therefore 620= H_(C-C) +6H_(C-H)`
`therefore H_(C-C)=620 -540`
= 80 kcal